Apparatus for use in vulcanizing pneumatic-tire casings for vehicles.



. E. HO PKINSON. APPARATUS FOR USE IN VULCANIZING PNEUMATIC TIRE CASINGSFOR VEHICLES. APPLICATION FILED FEB. 26. 1918.

'1,289,773. Patehted 'Dec. 31,1918@ UNITED STATES PATENT OFFICE.

ERNEST HOPKINSON, Oi NEW YORK, N. Y;

APPARATUS FOR USE IN vULoANIzING' PNEUMATIC-TIRE CASIN'GS FOR v'EHIoLEs.I

Specification of Letters Patent.

Application filed Ifebruary 26, 1918. Serial No. 219,234.

To all an hom it may concern Be it known that I, Ennns'r IIoPKINsoN,

a citizen of the United States, residing in New York city, county andState of New York, have invented certain new and useful Improvements inApparatus for Use in Vulcamzmg Pneumatic-Tire Casings for'vehi- -cles,of which the following is a full, clear,

and exact description, I,

This invention relates more particularly 'to apparatus for use invuloanizing pneuand for supporting it interiorly during .vul-

canization.

Referring to the drawings forming part of this specification:- Figure 1is a transverse sectional view of a preferred embodiment-of myinvention, Fig. 2 is a fragmental perspective'of the tire supportingrim. forming part of my invention. and I Fig. 3 is a fragmentaltransverse sectional viesykofa modified form ofthe invention.

Iii this method wherein fluid pressure is applied directly to theinterior of the easing. it is necessary to provide means for cooperatingwith the casing to form a closure suitable for the maintenance of thedesired fluid pressure for bringing the tire-to complete formation andfor maintaining itimder the required pressure during vulcanization andit is the object of my invention to provide suitable means for attainingthese results.

Pneumatic tire casings are ordinarily composed of fibrous materialassociated with rubber-and it is the usual practice to protect thefibrous component by havingthe entire.

exposed surface of the casing both internally and externally formed ofrubber. ;-Thisprevents moisture and; other injurious agents fromentering the fiber and also.prevents the wear by friction which thefiber might be subjected to if it were exposed on the surface of thecasing.' The coating of rubber on the interior wall of-the casing isusually comparatively thin. being ordinarily about .005 of an inch inthickness. In order to produce a satisfactory easing. it is importantthat this thin layer of ruhber cover- U mg the interior of the casing,sh ould remam' in perfect condition in the final product. that is to sayit should present no blemishes throughout its entire area. Moreover inthis method of vulcanization wherein fluid is directly applied to theinterior of the casing, it is of special importance that this thinunvulcanized layer of rubber should not be disturbed, for abrasions ofthe surface will expose the fiber beneath. and I have found PatentedDec. 31,1918.

that when this occurs the, fluid applied to the interior of the casingenters the exposed fiber and works its way into the body of the rubberand fiber wall composing the easing and often in this way reachesthe'most remote parts. When the fluid is permitted to enter the body ofthe casing inthis manner, 1t results in separating the plies composingthe casing producing blisters throughout rial and rubber about wirerlngsthard rub bcr cores, and the like, and whether this or some othermethod be pursued, these portions usually, on account of theirbulkiness,

the structure and in general producing havoc rigidity, reduction indiameter, etc., as compared to other portions of the casing, presentmore or less surface irregularities. As

it is at these portionsthat the closing means is preferably applied.another important feature of my invention 1s to provide a closing meansthat will not only operate without injury to the thin layer of nubber asbefore mentioned, but will also be-capable of lending itself to thesurface irregularities of the engaging surface, and-ithereby form anadequate seal to prevent harmful'escape of the fluid from the chamberformedwvithin the casing. Ff

r In the preferred embodiment of my invention, the closing means whichcooperates with the casing to form, afiuid chamber is provided witha-"cushioning face that will prevent abrasion[of the rubber surface of,the casing-and the resulting exposure of the fiber applied beneath.While the sealing means may be applied to any-desired part of the jointbetweenthe closing'means and easing, I prefer to provide a single meansfor. the closure and the sealing means for preventing the escape of thefluid.

Fig.1 illustrates one embodiment of m invention and Fig. 3 amodification there'o that will serve both as a cushioning face Theclosure for the casingsl' of Fig-1 comprises a portion 2 which extendsinto the casing to span the gap between the edge porwith to form afluidchamber," and a portion tions thereof and which cooperates there- 3extending laterally on either side forengaging the casing exteriorly bnits inner cir- ,cumference. The portion 2 is preferably in the form ofaclosed ring and the portion 3 is in the formof a rim disposed inanddetachable from the ring 2. Therini is preferably broken by awedge-shaped opening which is adapted'for the reception" ofa k'eyoperates in an obvious manner'to e and the rim for compressing theedgeso the atelier of the casing during thepvulcanizin'g treatment, andwhen such a step is a? casing to give them'the desiredv diameter of thefinished tire. A tube 8 is secured in the ring 2 which may be connectedwith a y" suitable source for [supplying the fluid to' the chamberwithin the casing; a

It is usually desirable to confine the exto, the usual cloth wrappingsorany, means may be employed as desired count of the characteristics betioned. it is" usually 1 desirable "hf provide rigid walls within which'tions and smoothing out the irregularities I thereof. The facin andsealing means be fore referred to is t erefore preferably a plied to thecasing-engaging-faces of t a ring 2 and is conveniently in the form ofbands 12. It will be readily 'understood that tdprovide a suitableclosure, which will form a fluid-tight joint without disturbing therubbercoverin 'of the casing, an important and diliicu t problem ispresented, especially when, from a practical standpoint, it is alsonecessary to provide an apparatus simple and comparatively inexpensivein construction, and comparativelyin expensive cushioning and sealingmeans easily applied and positivein operation to insure perfect tiresbeing produced; p

I have found that a plastic, such as unvulcanized'rubber; meets all theabove men tioned requirements and produces entirelysatisfactoryfresults'. Theplastic is preferably vreduced to strip forminany preferred fac'es-of the ring These faces'are prefer ably providedwith channels'13 for receiving the plastic I strips which facilitatesholding or we'll-known mannerand appliedto the them in pla'ceuntil theassemblage of the casing and other parts is efl'ccte'd. The sur- Lfa'ceof the rubber strips may be covered with any of the well kn'ownsubstances such as 'talo', starch, and the like-.for preventing theirvulcanization to the contacting rubber surface of 'the casing. 'Toobtain the best results a fresh rubber strip'should be used I witheachti're'. but this'does not represent a otal lossof the used ships as theymay be confine} mixed in rubber compounds for other uses.

the edge portions of the .I prefer however; to use the cheapest grade'canization so that as they expend?" iderthe/ heat of vulcanization theassa eima im;

plies composing the edge portions andjin moving or minimizing thesurface 'irregu- 'lanties In my preferred embodiment, 'I

atedwill result in compacting the? inany I therefore provide exteriorrigid walls which in the present instance are represented by the moldsections 9-9 which maybe of any usual or preferred construction. Thesections are channeled to engage the rim 3 as shown. and coiiperatetherewith to form a. complete closure for the casing. As a ready Thisfeature forms no r I As before mentioned. the, ring 2 prefer ablvextends into the casing as itthus'se'rves to limit the inward movementof the edges cooperating with the external; confining means forcompacting the said edge por-f ture. of the tireandafifords a readymeans for "of rubber compound or other suitable plastic that will servethe intended'purpos'e \in'order to reduce the cost to a minimum.Moreoverthe cheaper grade'of plastic will have less power'to vulcanizewith thecontacting rubber surface'of the casin and is thereforedesirable for this reason a so. I have found thnt'even thoiigh theplastic does not'produce a perfe't seal when the parts are firstassembled and the fluid pressure is applied that'this is corre ted whenthe heat of vulcanization is'applied. Under F i 'this heat. the plasticbecomes semi-fluid and means of holding the scctionstogetherp. lh/morereadily conforms to the irregularities of the adjacent surfaces.Moreover the ed L'e portions'of the casing; losing'much of theirrigiditv under .this'heat' and being under thein fluenveof the rigidsurrounding walls. lose much of their original irregularity the(EXDflfiSlOflfOf both the edae portions and therehy aidingin theforming" of a more perfectfjoint. 'whi -his further in reased by v)theplastieseahdue to thenise inPtempera l'have found that satisfaotorvresults are obtained by formingthe channels or rc'csses asrcpt-calcined. at 13 as they provide for an .to combine the two with aloose working between the rim :3 and the edges of the casing, for asbefore remarked, the rim 3 is previously expanded to firmly pressagainst the edge portions, which pressure is later increased by theexpansion of thecasing under the heat of vulcanization.

It will be noted-that the ring 2 and rim 3 are independent of each otherand I prefer fit even when the rim has been expanded so that the ringWlll serve as a floating member -to insure centralization thereof andequali- -zation of pressure upon the'edges of the casing. I

Fig. 3 illustrates a closure l i wherein the ring and rim are formedintegrally and while I prefer the embodiment shown in Fig. 1 for thereasons alreadv stated and because the parts are more easily assembledwith the casing, nevertheless the modified structure of Fig. 3 may bensedif desired.

As other embodiments of this invention may be made without departingfrom the spirit thereof, it isto beainderstood that I do not intend tolimit myself to the specific form of embodiment of the invention hereindescribed.

' Having thus described my invention, what I claim and desire to protect.by Letters- Patent is: v r

. 1. Apparatus for use in vulcanizing tire casings havingan exposedrubber surface forming a part.- thereof covering plies of fibrousmater-inland rubber. whichcomprises a closure adapted to coimeratc withthe exposed rubber sin-face forming the interior of the casing to formwalls defining a fluidtight chamber. said closure having cushioningfa'ees for dire tly engaging the .casing for sealing the, jointtluxrebetwecn and for protecting the exposed rubber surface adjacent.thereto to prevent abrasion thereof by the closure and the resultingexposure of the fiber ply beneath. and means for introducing fluid intothe chamber. i

2. Apparatus for use in vulcanizing tire casings having an exposedrubber surface forming a part thereof centering plies of fibrousmaterial and rubber, which comprises means for supporting the exterioredge portions of the casing, a closure adapted to cooperate with theexposed rubber surface forming the interior of the casing to form wallsdefining a fluid-tight chamber. means for introducing fluid into thechemher, and a cushioning facing for the casingengaging-surface of theclosure for sealing the joint therebetween and for, protecting theexposed rubber surface adjacent thereto to prevent abrasion thereof bythe closure and the resulting exposure of the fiberply beneath.

3. Apparatus for use in vulcanizing tire casings having an exposedrubber surface forming a part thereof covering plies of fibrous materialand rubber, which comprises a ring adapted to cooperate with the exposedrubber surface forming the interior of-the casing to .Qform wallsdefining a fluid-tight chamber, said ring having cushioning faces fordirectly engaging the casing for sealing the joint therebetween and forprotecting the exposed rubber surface adjacent. thereto to preventabrasion thereof by the ring and the resulting exposure of the fiber-plybeneath, and means for introducing fluid into the casin 4. Apparatus foruse in vul anizing tire casings having an exposed rubber surface forminga part thereof covering plies of fibrous material and rubber. whichcomprises means for supporting the exterior edge portions of the casing,a ring adapted to cooperate with the c.X|')osed rubber surface formingthe interior of the casing to said ring having cushioning faces fordirectly engaging the casing for sealing the joint therebetween and forprotecting the exposed rubber surfac adjacent thereto to preventabrasion thereof by the ring and the resulting exposure of the fiber plybeneath. and means for introducing fluid into the chamber.

5. Apparatus for use in vulcanizing tire casings comprising a supportfor engaging the edges of the casing. a sealing member of yieldingmaterial tor rendering the interior of the casing fluid-tight. means forexpandform walls defininga fluid-tight chamber,-

ioning faces for engaging the casing for scaling the joint thcrebctwtwnto cooperate therewith to form a. fluid chamber and lat erally extendingportions adapted to engage the casing cxteriorly at the edge portionsthereof, an exterior mold engaging the laterally extending portions ofthe support for forming a complete inclosurc for the casing,

and -means for introducing fluid into the chamber.

7..Apparatus for use in vulcamzing tire "casings comprising a rinadapted to engage the interior of the casing and provided withcushioning faces for engaging the casing for sealing the jointtherebetween to cooperate therewith to form a fluid chamber, a rimwithin the ing detachable therefrom for supporting the edges of thecasing, and means for introducing fluid into the interior of thechamber.

8. Apparatus for use in vulcanizing tire casings comprising a ringadapted to engage the interior of the casing and to cooperate therewithto form a fluid chamber, a. rim

within the ring detachable therefrom for casings comprising a closurefor engaging the edge portions of the casing to form therewith wailsdefining a chamber. a facing for the casing-engaging-surface of theclosure formed of a material expansible under the heat of vulcanizationfor better conforming it to the irregularities of the adjacent surfacesto form a fluid-tight seal, and means for introducing fluid into thechamber.

11. Apparatus for use in 'vulcanizing tire casings comprising a closurefor engaging the edge portions of the casing to form therewith wallsdefining a chamber, a facing for the casing-engasing-surface of thec1osure formed of a material semi-fluid under the heat of vulcanizationfor better conforming it to the irregularities of the adjacent surfacesto form a fluid-tight seal. and means for introducing fluid into thechamher. v

12. Apparatus for use in vulcanizing tire casings comprising a closurefor engaging the edge portions of the casing to form therewith wallsdefining a chamber. a'facing of unvulcanizcd rubber for thecasing-engaging-surface of the closure, and means for introducing fluidinto the chamber.

13. Apparatus for use in vulcanizing tire casings comprising a closurefor engaging the edge portions of the casing to form therewith Wallsdefining a chamber having its engaging surfaces channeled, a facing ofplastic material disposed in the channels, and. means for introducingfluid into the chamber.

14. Apparatus for use in vulcauizing tire casings comprising a supporttherefor. having aportion adapted to extend into the in:

terior of the casing and spaced therefrom andlaterally extendingportions adapted to directly engage the casing exteriorly at the edge)ortions thereof, a facing of plastic material filling the spaces toform with the said support and easing a chamber, and means forintroducing fluid into the chamber. I

"'15. Apparatus for use in vulcanizing tire casings comprising meansprovided .with channels formed in oppositely disposed side walls thereoffor closing the gap between the edge portionsof the casing forcooperating with the casing to form walls defining a chamber. means forintroducing fluid into the chamber, and sealing rings of rubberengageol'hy said. channels for the chamber.

16. Apparatus ,for use in vulcanizing tiredirectly engaging the casingto prevent the escape of fluid from ing the edge portions interiorly forcooperating with the-interior or" the casing for forming a dual chamber.and means formtroducing fluid into the chamber.

Signed at New York city, New York, this 21st day of February. 1918.

ERNEST noercnison.

